Endocrine Flashcards
What dose of insulin (weight based) should be started for an insulin naive patient?
A. 0.01 - 0.02 U/kg/d
B. 0.2 - 0.3 U/kg/d
C. 0.1 - 0.2 U/kg/d
D. 0.05 - 0.1 U/kg/d
C. 0.1 - 0.2 U/kg/d (roughly 5-20 units)
If AM fasting glucose has increased or decreased by at least ______% from the night glucose, you should change the basal insulin dose.
15%
What dose of levothyroxine should be started in hypothyroidism?
A. 1.6 microgram/kg lean body weight
B. 0.7 microgram/kg lean body weight
C. 1.6 microgram/kg actual body weight
D. 0.7 microgram/kg actual body weight
A. 1.6 microgram/kg lean body weight
You have a new patient with hypothyroidism and you are starting levothyroxine. What should you start at for a 40 yo woman who weighs 65 kg lean body weight?
100 micrograms daily
What dose would you start for levothyroxine in a 75 year old at 55 kg woman with PMH T2DM, CAD s/p PCI 2 years ago, and CVA?
25 - 50 micrograms per day (due to higher age and CV disease history)
What labs should you get in a male prior to starting him on testosterone?
Hbg/Hct and PSA
How do opioids affect the HPA axis?
decrease gonadotropin, increase prolactin
What medical history would make you choose against an SGLT-2 inhibitor? List up to 7.
- previous amputation
- severe PVD
- active diabetic foot infection/ulcers
- severe peripheral neuropathy
- genital fungal infections
- UTIs
- euglycemic DKA
If an adrenal mass is identified on CT, what two tests should you always get?
Cortisol and potassium
If an adrenal mass is identified on CT, what would make you screen for A) hyperaldosteronism, or B) pheochromocytoma?
A) HTN or hypokalemia
B) unenhanced CT attenuation of at least 10 Houndsfield units
If an adrenal mass is identified on CT, cortisol is negative, and the patient is asymptomatic (no HTN or hypokalemia) with benign imaging, what do you do next?
Clinical observation vs repeat CT at 12 months
In hyperandrogenism with slightly elevated testosterone and elevated DHEAS, what source is suggested and what imaging test should you perform?
This testing pattern suggests adrenal source and you should get a CT abdomen
If a patient has signs of hyperandrogenism, what two blood tests would be helpful to determine the source?
Testosterone and DHEAS
In Hyperandrogenism, what may distinguish ovarian from adrenal source in labs?
Testosterone will be a lot higher in ovarian vs adrenal tumor. slight elevation in testosterone if just PCOS.
What labs are elevated in Cushing’s disease?
cortisol and ACTH
What differentiates thyroid storm from thyrotoxicosis?
Thyroid storm has life-threatening complications
In treating thyroid storm, what is one special consideration in order of treatment?
PTU should be started at least 1 hour prior to giving potassium iodide (KI).
What 4 main treatments are given for thyroid storm, and what other medication may be helpful?
Esmolol, PTU (propylthiouracil), KI, high dose IV steroids. Cholestyramine can be helpful as it decreases T3 and T4 levels.
If medication treatment of thyroid storm fails, what happens next?
If all else fails, plasmapheresis or emergent thyroidectomy.
How and when is Vitamin B12 monitored in long term metformin use?
Should be checked annually if someone has been on it for at least 5 years.
When should you check T3?
When clinical thyrotoxicosis is present and T4 is normal.
What are the symptoms and possible lab findings of osteomalacia?
Aching bone pain in lower back, pelvis, and legs which is worsened with weight bearing. Elevated alk phos. May have low Calcium, phosphorus, or Vitamin D.
What is the problem in osteomalacia?
Inadequate bone mineralization
What class of medications can trigger hyperprolactinemia?
Antipsychotics
A patient presents with irregular menstrual cycles after being started on risperidone 2 months ago for bipolar disorder with psychosis. What is the problem, and how do you treat it?
Hyperprolactinemia. Treatment is Estrogen-progesterone replacement. (cabergoline could induce psychosis).
What would be a contraindication to treating hyperprolactinemia with cabergoline?
If the condition is caused by antipsychotic, could induce psychosis by starting cabergoline
What is the mechanism of action of cabergoline?
Cabergoline: Dopamine agonist.
How does dopamine affect prolactin? vise versa?
Dopamine inhibits secretion of prolactin. Prolactin levels rise and promote dopamine release to regulate itself.
Sort the following osteoporosis medications by group (antiresorptive vs anabolic):
- Denosumab
- Teriparatide
- Bisphosphonates
Denosumab and Bisphosphonates are antiresorptive agents. Teriparatide is an anabolic agent.
How should you finish treatment with teriparatide for osteoporosis?
Do not stop it without adding on an antiresorptive agent to prevent bone loss.
How do you diagnose Cushing syndrome?
Need 2/3 of the following:
- overnight low-dose dexamethasone suppression test
- 24-hour urine free cortisol
- late-night salivary cortisol
Once you have diagnosed Cushing syndrome, what do you do next in diagnosis?
measure ACTH
You have just diagnosed ACTH-dependent Cushing syndrome. Now what?
Find the source: Pituitary MRI, then if negative high dose dexamethasone test which will tell you if it is from the pituitary or not.
What does it mean if you still have high cortisol after a high dose dexamethasone test in ACTH-dependent Cushing syndrome?
ACTH is not from the pituitary
What test is next in ACTH-independent Cushing syndrome?
Adrenal CT
What factors would make you order a DEXA scan in a young adult with a low-energy fracture?
- Recurrent fracture
- High risk conditions present such as: Eating disorder, Organ transplant, Steroid treatment
How do you diagnose PCOS?
- Exclude other causes increased androgens
- Need 2/3 of the following:
-oligo/anOVULATION
-clinical and/or biochemical signs of HYPERANDROGENISM
-polycystic ovaries on ULTRASOUND
A young female patient comes in complaining of excess hair above her upper lip and on her chin. She has regular menstrual cycles. You test testosterone and it is elevated. Can you diagnose PCOS?
No, should get DHEAS, cortisol tests for cushings, 17-hydroxyprogesterone for nonclassic CAH and rule out other causes of hyperandrogenism. If you do that, you still only have 1/3 (clinical/biochemic signs hyperandrogenism) and since her cycles are regular you now need a pelvic ultrasound to look at the ovaries.
What are signs of virilization?
Voice deepening, male pattern baldness, acne, clitoromegaly
What are causes of hyperandrogenism?
PCOS, ovarian/adrenal/pituitary tumor, Cushing’s syndrome, non-classic CAH
How do you evaluate someone with gynecomastia?
Check for testicular mass. Test 8am total testosterone, hCG, LH, estradiol.
You perform a radioactive iodine uptake scan and find that uptake is 30% over the whole thyroid. Which of the following conditions is most likely?
- Graves disease
- Destructive thyroiditis
- Toxic nodular goiter
Most likely Graves. The other two conditions usually have <10% uptake.
A patient with hyperthyroidism has been admitted to the hospital for 1 week and begins to have sudden symptoms of palpitations, sweating, anxiousness. You check a T4 and now it is elevated although she has been on a stable dose of PTU for a year. What happened?
Probably got iodinated contrast exposure on admission. Can trigger thyrotoxicosis after 1-2 weeks.
Why does subclinical hyperthyroidism matter?
increased risk of afib, CV events, hip fracture. Need to treat if TSH persistently suppressed.
What are the indications for parathyroidectomy in an asymptomatic patient with hyperparathyroidism?
Age, bone, kidney, calcium.
-Age <50
-Osteoporosis on dexa
-CKD3 or worse, nephrolithiasis or increased risk stones
-Serum Ca at least 1 above ULN, 24 h urine Ca >400
A patient comes to you with primary hyperparathyroidism. She is asymptomatic. Age 55, no history of osteoporosis or kidney stones. Labs with serum calcium 11 (normal ULN 10.5), urine calcium 24 h excretion 455, GFR 52. Should you refer her for surgery?
Yes, based on excretion of urinary calcium and GFR
List causes of hypoglycemia
- DM
- Medications
- Liver or kidney dysfunction
- Malnutrition
- Adrenal insufficiency
- Roux-en-y bypass
- Insulinoma
- Endogenous hyperinsulinemic hypoglycemia
How do you work up hypoglycemia?
Initial:
-insulin antibody
-oral hypoglycemic agent screen.
-Do a 72-hour fast, and if get hypoglycemic confirmed on BMP (symptoms with glucose <45, or <55 but symptoms improve with raising glucose),
Then send:
-C-peptide
-insulin
-pro-insulin
-beta-hydroxybutyrate
What is whipple’s triad in hypoglycemia?
symptoms, glucose, resolution.
symptoms when glucose is <55 which improve with raising of glucose
What are the two types of amiodarone thyrotoxicosis? How would you differentiate the two types by imaging?
- Type 1 (underlying Graves or nodules triggered). Type 2 (new destructive thyroiditis).
- Doppler ultrasound (Type 1 has increased vascular flow).
How would you treat destructive thyroiditis triggered by amiodarone?
Self-limiting, could do steroids if tenderness not resolved with NSAIDs
Treatment for Paget disease of bone?
Antiresorptive (bisphosphonate or denosumab)
When to consider PSA testing for men?
High risk age <55, average risk 55-70 biennial based on conversation.
Who might have calcium malabsorption?
Celiac disease, bariatric surgery
What medications may help with hirsutism?
OCPs +/- spironolactone
Treatment options for diabetic neuropathic pain
gabapentinoids, NSRIs, TCAs, Na-channel blockers
Female infertility work up for irregular menses
Mid luteal phase serum progesterone and if normal then hysterosalpingography to check for tubal patency and uterine abnormalities
